make module and file naming consistent
Our src/gromacs modules are named inconsistently when the name has more than two words. The "complexname" pattern can be hard to read, but is somewhat consistent with class naming. The "complex_name" pattern is familiar and is preferred at https://google.github.io/styleguide/cppguide.html#File_Names. The "complex-name" pattern works and saves a shift key press. The "ComplexName" pattern works but might be tricky if we would ever again encounter a non-case-sensitive file system (albeit that we already use case in naming short-range kernels and reference data files).
Names of files within modules should also follow a particular pattern. We should avoid short file names likely to be present in multiple modules (logging.h, util.cpp, etc.). Once a module has a conforming design, then the file names should anyway relate to the class being implemented in them. In some cases that will mean the module name is a prefix for the class name, and thus file name. So we should expect to find the NbnxmGridSearch class implemented in src/gromacs/nbnxm/nbnxm_grid_search.cpp.
#1 Updated by Mark Abraham 29 days ago
At https://gerrit.gromacs.org/#/c/9021/, Mark preferred consistency, then readability, and doesn't care what we choose. Also there, Roland preferred that we use only one of dash and underscore and observed that there are names including acronyms that are particularly hard to read. At https://gerrit.gromacs.org/#/c/8940/, Szilard preferred underscores. Berk didn't express an opinion. Erik's kernels have had both underscore and case, so he'll cope.
That sounds like the "complex_name" pattern has broad support for module naming.
For naming files within modules, are we OK with things like src/gromacs/listed_forces/gpu_bonded_impl.cu?
I'll put together an updated entry in the style guide if people give me a bit of feedback.